Modern standards of fire precautions are based on a broad view of the ultimate objective: to minimise risk to life and property. The behaviour of materials and structures in fire is one factor, the availability of fire brigades, of fire extinguishers and alarm equipment in buildings etc, are others. This Digest is concerned only with the first: the characteristics of materials and structures that enter in the design of buildings from a fire protection standpoint. These are the combustibility of materials, flame spread on surfaces, and the fire resistance of elements of structure. The combustibility of various wall and ceiling linings and of different roof materials is discussed.

Table 1 shows the spread-of-flame classification of combustible wall and ceiling linings (British Standard BS476 part 1). Table 2 gives the performance of boards tested in fully-lined rooms.